Kneading machine for margarine and the like



28, 1936. A. GERSTENBERG KNEADING MACHINE FOR MARGARINE AND THE LIKE Filed Aug. 5. 1933 65465 65/75 TENBERG Patented Apr. 28, 1936' UNITED STATES PATENT OFFICE KNEADING CHINE FOB AND THE LIKE Aage Gatenberg,

pp ication smut 5, less. Serial No. man InDcnmarkAugust 16, 1932 9 Claims. (oi. 31-45) kneader worms or kneader rollers, by means of which the substance was treated. These open kneading machines were subject to various drawbacks and disadvantages, among which for instance was the fact that they were not continuously operative. The demands for greater economy and a more hygienic manufacture of food stuffs brought about a gradual change to the use oi wholly or partly closed kneading machines. which oil'ered the hygiene and the operation.

Continuously operating wholly or partly closed' kneading machines, however, have thus far proved open to the objection that the rather large quantitles of air contained in or adhering to the loose product coming from the cooling drum and having to be kneaded cannot escape during thekneading process, for which reason the finished product contains numerous fine air bubbles. These air bubbles have a spoiling eifect, such, for instance, that margarine treated in continuously operating kneading machines of the kinds heretofore known, will get the appearance of having been greatly discoloured during the kneading process.

Attempt has been made to avoid this drawback attainment of a continuous by adding more colouring substance to the margarine. As the latter, however, as a rule after the kneading, has to be packed by means of a packing machine, it will thereupon be exposed to a compression eifect whereby a part of the air bubbles will burst. Accordingly the parts of the margarine where this happens will again assume their original colour, with the consequence that the finished packed "margarine will have a spotted or striped appearance, whereby its value as a commercial commodity will be reduced.

' been tried to avoid discolouring of margarine dur- This circumstance is well known, and it has ing the kneading by performing the latter in hermetically closed vessels or. chambers exposed to a partial vacuum, whereby the air in the margarine will be removed. This method of kneading under vacuum, however, is highly complicated and costly, and involves additional work by precluding a 56 continuous operation. of margarine possibility of more satisfactory in hermetically closed kneading machines can in fact be eflected only by discontinuous operation, in which a suitable quantity of margarine is placed in a closed chamber, after which the latter is closed hermetically. The said chamber is then exposed to a partial vacuum, and thekneading .is

then as a rule carried out durlngth'e course of two to five minutes. The operation must then'be pped, the apparatus opened, the margarine removed and a fresh quantity of margarine put in. This manner of operation is obviously very uneconomical.

The present invention has for its object to avoid this drawback by a novel combining of continuously operating kneading machines with means for reducing the air pressure in one'or more parts of the kneading chambers, during the continuous operation.

A condition to be fulfilled where the air contained in the margarine or introduced therewith into the kneading machine is to be removed from the margarine during the kneading, is, that the, substance under treatment shall be caused, at 7 two or more places, to fill completely the free passage area through the kneading apparatus, and to provide, with respect thereto or between any two of such places, a region in the kneading machine in which a reduced pressure can be created by an exhaust of air by way of a vent opening provided, for the region concerned, in the casing of the. kneading machine.

In order that the substance under treatment shall not obstruct the vent opening, it will ordinarily be necessary to relieve the pressure on the substance around the location of said opening by providing, in the said reduced pressure region, a conveyor member actuating the substance and moving the same away from the said opening and, thereby, causing the substance around the opening to be entirely relieved from any pressure.

In order to secure an air-tight sealing of the passage area in the kneading apparatus, resistance members are provided before and behind the region concerned from which the exhaust is to be dictated, substance being pressed against the said resistance members by the kneader members orother devices for moving the substance forward,

in such a manner that the substancewill accumusuction pump or some other suitable suction device adapted tomaintain continuously a partial s5 vacuum suited to the removal of the air from the substance under treatment.

The further details of the invention will appear from the Iollowing description of the constructions or a kneading apparatus embodying the same, as illustrated by the attached drawing.

Figs. 1 and 2 somewhat diagrammatically represent longitudinal sections of two diflerent constructions of a kneading machine according to the invention,

Fig. 3 is a cross-section of the kneading ma chine shown in Fig. 2, taken on the line III-III thereof,

Figs. 4 and 5 are respectively, a longitudinal section and a cross-section of a third construction of a kneading machine, the former being taken on the line IV-IV of the latter and the latter being taken on the line V'V of the former; and

Fig. 6 is a section on the line VIVI of Fig. 2, illustrating a detail.

Reierring first to Fig. l, a is the supply hopper of continuously operating kneading machine, which mainly consists of a casing o with kneader members b, c, e, Z, of known kind provided therein. The margarine or other fatty substance to be treated is introduced by way of said hopr a and is pressed by the worm E) into a narrow an nuiar space y formed between the kneading nien1- bers 0 comprising rotary disc-shaped elements carried by the worm shaft, and stationary an nular ring or partition members q provided inside the casing. The margarine will accordingly entirely fill said space y under pressure from the worm b forcing it therethrough. Under the passage through this space the margarine is subjected to a kneading by the action of said rotary members c working against said stationary members q, after which kneading the consistency of the substance will be or such a nature that -a removal of the air from the same can take place readily.

From the kneader members 0, the margarine passes into a chamber d, where it is caught by a worm e, which forces the same through openings f in one or more resistance bodies a: provided in the kneading machine. These openings 1 are of such a size that the resistance they offer against the passage of the substance is sufiiciently high to cause the substance, while actuated by the worm e to fill the passage area completeLv, and at the same time, the air bubbles in the margarine will be compressed and broken up, whereby the air in these bubbles will be released and discharged into an escape passage 0, by way or which the chamber d communicates for instance with the atmosphere through a vent opening or pipe i. In order to facilitate the removal of the air, this vent opening or pipe is generally connected to a suction pump (not shown) or to some other suitable device for sucking away the air, such for example as the rotary exhauster device W shown connected by pipe to to the nipple i in Figs. 3 and 4. The opening a itself is closed by a cover h, in which the vent pipe i is formed or to which it may be connected.

The aforementioned resistance bodies a: in which the openings I are provided, may be of various constructions known per se, or may be replaced by one or more restricting means in the partotthecasingotthekneadingmachincwhere the partition walls are provided in the construction shownin the drawing. Aiter the margarine oristtysuhstoncehaspassedthroughtheopcninssflitmayberurthcrtreatedtoireeairthcre- Emily sealed.

from by again subjecting it to such mechanical working as by similar kneading means comprising the worm 1 serving to press the substance through openings m in a transverse partition disposed in the kneading chamber behind said worm l. The part is of the casing of the knead ing machine in which this worm Z is situated would then be fitted with an escape passage 11 similar to the passage g for the same purpose.

The worms e and l, of which the latter may if desired be omitted together with its corresponding part of the casing of the kneading machine, are constructed as conveyor worms with such a pitch and capacity for conveying the substance as to carry it past the air escape passages a and 12. without mrmitting any part of the substance to be pressed out through said passages or their associated vent openings.

In certain cases it may be desirable to provide several air escape passages (like 9 and n) in succession at various points of the movement of the substance through the kneading machine if desired, such several passages may be so formed associated vent openings and suction con necticns as to provide unequally reduced pre"- sures in the various parts of the kneading ma chine, commencing with a relatively high removing suction at one end and gradually ire-- ducing the same toward the other end 01 machine. Hereby the advantage can be attained that all the conveyor members (the worms e,

Z will have mainly the same back pres are to overcome.

The construction shown in Figs. 2 and 3 difiers from the one shown in Fig. l in that the worms e and 2 and the kneading members 0, together with their corresponding parts of the casing of the apparatus are omitted. In this construction the removal of air is effected by way of a vent opening or nipple 9 (corresponding with the opening or pipe 1 of Fig. 1) formed in the wall 0! the casing 0 surrounding the worm b. This opening or nipple 1' is intended to be connected through suitable piping w with a suction device or pump W like its corresponding part in Fig. 1. The mass to be treated is supplied to the worm b by means of two feed rollers u and 12 provided in the hopper a, and is pressed by said worm b through the openings f of the resistance plates 2:, between which rotary kneader members 9 in the form of radially disposed paddle blades (see Fig. 6) are disposed. By way of said nipple 1' with its suction connection, a partial vacuum of, suitable magnitude is produced in the interior of the kneading machine. While actuated by the feed rollers u and v the substance will form an air-tight seal between the rollers themselves and between said rollers and the inner face of the hopper a. 4 a

The construction shown in Figs. 4 and 5 diifers from that shown in Figs. 2 and 3, mainly by the feature that the feed rollers u and v are replaced by worms 3 and t, and by the feature that the nipple is in this instance disposed in the kneading chamber a in front of the supply opening or feed passage 1', by way of which the substance is conveyed from the hopper a to the worm b. Said nipple i may be connected with a suction pumpW (seeFig.4) thesameas-inl'lgJ. The substance itself maintains the opening 1' air- A feature common to all the aioredescribod constructions is that the ventopenins i or its equivalent nipple 1. throush which the sir from the kneader members is dischsrscdormcked" away, is disposed in such a manner, relatively to the conveyor devices for the substance worked upon by the apparatus concerned that the said conveyor devices move the substance away from the air escape passages and thereby prevent the substance from entering into the same so as to close them or leak out.

In the machines described, all the rotary members, excepting the feed rollers u and v and the feeder worms 8 and t, are disposed on one common shaft, but the scope of the invention will not be departed from constructing the machine with any suitable number of shafts placed side by side or end to end, either in a separate chamber or all in the same chamber.

In comparison with the heretofore known continuously operating kneading machines, the machines herein set forth offer the advantage that they simultaneously perform the kneading and remove the air from the margarine, in such a' manner that the latter retains its colour unaltered, or substantially. unaltered, and will appear as a uniformly coloured product.

If the margarine, before being introduced into the kneading machine, has been subjected to a preliminary kneading, then the kneader members c and perhaps also the worm b may be omitted, or else the number of kneader members may be reduced.

Having now particularly described and ascertained the nature of my invention and in what manner the same is to be performed I declare that what I claim is:

1. A kneading apparatus for margarine and the like material, comprising a casing having a feed inlet and outlet, means provided in the casing for kneading the material so as to liberate air therefrom, means providing for the expulsion of the liberated air from the casing as it is forced out of the material by the kneading action, and means permitting. a'continuous feeding and discharge of the material through the casing while subject to the air expulsion therewithin.

2. A kneading device for margarine and other fatty substances, comprising a casing having inlet and outlet openings, kneading members operable within the casing, means for creating a partial vacuum in the kneading space of the casing, and means permitting a continuous feeding and discharge of materialthrough the casing while under vacuum therewithin.

3. A kneading device for margarine and the like, comprising a casing having a feed inlet and outlet. means for kneading the material within the casing, means provided for the suctional withdrawal of air from a part of the casing where the kneading occurs, and means permitting a continuous feeding and discharge of the material through the casing while under said suetional action therein without allowing any of the material to be drawn into the suction passage.-

4. An apparatus for kneading margarine and the like in a continuous operation, comprising a casing, a number of kneading members including rotatable parts mounted in the casing, a vent opening in the wall of the casing adapted for connection with a suction device and means permitting continuous feeding and discharge of the material while under vacuum within the casing created by the suction device; said means being adapted to prevent the material from penetrating stance, a suction device connected with said openfleeting-the substance in its continuous passage into the vent opening during its passage through the apparatus.

5. A device for kneading margarine and the like in a continuous operation, comprising a casing, a number of kneading members including 5 rotatable parts mounted therein and through which the margarine is passed through the easing, an inlet through which the material is supplied, an outlet through which the material is discharged, and a vent opening in the wall of the casing; said opening being located in advance of the kneading members which remove the material from the region thereof simultaneously with the airexpulsion therethrough so as to prevent the material from entering'the same.

6. An apparatus for kneading fatty substances such as margarine and the like in a continuous operation, comprising a casing having an inlet and an outlet, kneading means including a motivating member rotatably mounted in the casing and I having associated means for driving the same, a vent opening in the wall of the casing permitting the expulsion of air therefrom during the action of the kneading means upon the subing, and means including said motivating rotatable member for continuously feeding and discharging the substance through the casing while under the action of said suction and at the same time preventing the substance from penetrating go into said opening.

opening air from the substance is drawn while the substance is forced in a forward direction so as to completely fill the space between said 40 member locations without itself being drawn through or into said vent opening, and means permitting continuous feeding and discharge of the substance through the machine while under such air drawing action. 45 8. The method of preventing discoloring of Y margarine in a continuous kneading operation, which consists in feeding the margarine continuously'into a closed casing having kneading members therein and continuously discharging the kneaded margarine from the casing, subjecting the margarine to a vacuum for the withdrawal of air therefrom while in its passage through the kneading members in continuous feed and discharge through the easdrawn from the machine by the action of the vacuum so applied.

9. The method of preventing discoloring of margarine or other fatty substances in a continuous kneading process, which consists in continuously passing the substance through a machine performing a kneading operation thereon, sub

to a vacuum during the kneading operation there- 'upon in order to withdraw air from the same and simultaneously preventing any of the substance in passage from being drawn from the machine by said vacuum. 7o

AAGE GERS'I'ENBERG.

55 ing,, and preventing the margarine from being 

